Azeotrope-like HFC-245cb and HFO-1225ye Mixtures
Solution Overview
Problem
The industry faces challenges in identifying new, environmentally safe fluorocarbon-based mixtures with low global warming potential and ozone depletion potential, as azeotrope formation is not readily predictable, and existing technologies lack azeotrope-like compositions that can replace chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) in applications like refrigerants and aerosol propellants.
Innovation Solution
Development of azeotrope-like compositions comprising 1,1,1,2,2-pentafluoropropane (HFC-245cb) with either the Z isomer of 1,1,1,2,3-pentafluoropropene (HFO-1225ye(Z)) or a mixture of the E and Z isomers of 1,1,1,2,3-pentafluoropropene, which exhibit constant boiling points and cannot be separated during phase changes, making them suitable for use as refrigerants, aerosol propellants, and blowing agents.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If new fluorocarbon-based mixtures are developed to replace CFCs and HCFCs, then environmental safety is improved, but azeotrope formation becomes unpredictable
Solution Approach 1:
The patent applies parameter changes by systematically varying the compositional parameters of fluorocarbon mixtures (specifically HFC-245eb and HFO-1225ye isomers) to identify specific ratio ranges that produce azeotrope-like behavior. By changing the concentration parameters within defined ranges, the invention transforms the unpredictable azeotrope formation into a controllable property with predictable thermodynamic states.
Solution Approach 2:
The invention creates composite fluorocarbon mixtures combining HFC-245eb with specific isomers of HFO-1225ye (E and Z isomers) in predetermined ratios. These composite compositions exhibit azeotrope-like properties that are not readily predictable from individual component properties, yet provide environmentally safe alternatives to CFCs and HCFCs with low GWP.
2Stability of the object's composition
If single component fluids or azeotropic mixtures are used, then fractionation on boiling and evaporation is prevented, but identification of new mixtures is complicated
Solution Approach 1:
The patent defines specific compositional parameter ranges (e.g., HFO-1225ye(Z) at 5-50 wt% and HFO-1225ye(E) at 0-45 wt%) that guarantee azeotrope-like behavior and non-fractionating properties. By establishing these quantitative parameter specifications, the invention simplifies the identification process while ensuring stable composition during phase changes.
Solution Approach 2:
The invention segments the complex mixture identification problem into manageable parts by separately specifying the concentration ranges for each component (HFC-245eb, HFO-1225ye(Z), HFO-1225ye(E)). This segmentation allows systematic formulation of azeotrope-like mixtures with predictable properties without requiring complex predictive models.
3Object-affected harmful factors
If fluorocarbon mixtures with low global warming potential are developed, then environmental safety is improved, but predictable thermodynamic state becomes difficult to achieve
Solution Approach 1:
The patent creates composite fluorocarbon mixtures combining HFC-245eb (low GWP) with HFO-1225ye isomers that exhibit azeotrope-like behavior. These composite compositions achieve both low global warming potential and predictable thermodynamic states through synergistic interactions between components that stabilize the vapor-liquid equilibrium.
Solution Approach 2:
By optimizing the compositional parameters within specific ranges, the invention achieves predictable thermodynamic states in low-GWP fluorocarbon mixtures. The parameter optimization ensures that the mixtures maintain stable boiling points and vapor-liquid equilibrium characteristics despite using environmentally friendly components.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
These compositions offer a viable alternative to CFCs and HCFCs with low global warming potential, providing a stable and non-fractionating mixture for various industrial applications, including refrigeration and foam production, while being environmentally safer and having a predictable thermodynamic state.
Implementation Method 1
azeotrope-like compositions of 1,1,1,2,2-pentafluoropropane (HFC-245cb) with either the Z isomer of 1,1,1,2,3-pentafluoropropene (HFO-1225ye(Z)) or with a mixture of the E and Z isomers of 1,1,1,2,3-pentafluoropropene
Implementation Method 2
exhibit constant boiling points and cannot be separated during phase changes
Implementation Method 3
U.S. Pat. No. 7,161,049 shows a process for purifying hydrofluoropropanes which may include HFC-235cb or HFO-1225ye, however, no azeotrope-like compositions thereof are disclosed. U.S. Pat. No. 7,077,960 discloses a process for the production of a hydrofluoroalkane, according to which hydrofluoroalkane comprising organic impurities is subjected to at least two distillations.
Data Source
AI summary
The present invention provides azeotrope-like compositions of 1,1,1,2,2-pentafluoropropane (HFC-245cb) with either the Z isomer of 1,1,1,2,3-pentafluoropropene (HFO-1225yeZ) alone or with mixtures of the E and Z isomers of 1,1,1,2,3-pentafluoropropene (HFO-1225 yeZ and HFO-1225 yeE) and uses thereof, including use in refrigerant compositions, refrigeration systems, blowing agent compositions, and aerosol propellants, and in process for separating azeotrope-like mixtures.